The present invention relates to a terminal device provided in an electrical apparatus such as an electromagnetic contactor, a molded-case circuit breaker, and a terminal base.
A terminal device includes a box terminal device with a box fitting for directly connecting an end of a cable, and a terminal device for connecting a cable with a press terminal at an end thereof. Japanese Patent Publication (Kokai) No. 2002-190331 has disclosed a conventional box terminal device.
FIG. 7 to FIG. 9 show a structure of the conventional box terminal device provided in an electromagnetic contactor. FIG. 7 is a vertical cross sectional view showing the box terminal device, FIG. 8 is a vertical cross sectional view showing the box terminal device in FIG. 7 in a state in which a cable is connected thereto, and FIG. 9 is an exploded perspective view showing the box terminal device in FIG. 7. In FIG. 7 to FIG. 9, particularly in FIG. 9, a terminal strip 3 having a box-shaped terminal fitting 2 is attached to a terminal section provided in a frame 1 made of an insulation material.
In the terminal section, insulation walls 4 are formed on right-hand and left-hand sides of the terminal strip 3. In each of the insulation walls 4 opposite to each other, a rectangular groove 5 (see FIG. 9) is formed in the direction from the front to the rear. A box-like space 6 is formed between the opposing insulation walls 4 for holding the terminal fitting 2.
Two projections 3a (see FIG. 9) are formed on each of the right-hand and left-hand sides at an end of the terminal strip 3. The terminal strip 3 is inserted into the grooves 5 from the front to the rear of the frame 1 with the projections 3a as shown by an arrow in FIG. 9. The terminal strip 3 is prevented from slipping off from the frame 1 with a pin 9 fitted to a bottom hole 8 in the terminal section through a through hole 7 (see FIG. 9) in the terminal strip 3. The terminal fitting 2 is formed in a box-like shape (rectangular) by die cutting and bending to be fitted slidably up and down to a recess between the projections 3a provided on each side of the terminal strip 3. A terminal screw 10 with a hexagonal head hole is screwed into a threaded hole at a top of the terminal fitting 2 with a square washer 11 loosely coupled to the end of the terminal screw 10.
In the terminal device, a stripped end of a cable 12 to be connected is directly inserted into both or one of the upper and lower sides of the terminal strip 3 to be held between the terminal fitting 2 and the terminal strip 3 by tightening the terminal screw 10. A fixed contact point is attached to a right-hand end of the terminal strip 3 (not shown).
FIG. 10 to FIG. 12 show a structure of a conventional terminal device for a press terminal provided in an electromagnetic contactor. FIG. 10 is a vertical cross sectional view showing the terminal device, FIG. 11 is a vertical cross sectional view showing the device in FIG. 10 in a state in which a cable is connected thereto, and FIG. 12 is an exploded perspective view showing the device in FIG. 10. In FIG. 10 to FIG. 12, similar to the box terminal device, a terminal strip 3 to which a terminal screw 10 is screwed in is inserted in a groove 5 in an insulation wall 4 formed in a frame 1. The terminal strip 3 is prevented form slipping off from the frame 1 with a screw section of the terminal screw 10 fitted into a cylinder-like recess 13 provided in the frame 1.
In the terminal device, a cable 12 with a press terminal 14 crimped onto its end is secured to the terminal strip 3 by the terminal screw 10 with the press terminal 14 tightened onto the terminal strip 3. A threaded hole of the terminal strip 3, into which the terminal screw 10 is screwed, has a lower opening processed by burring. A recess 15 is formed around the cylinder-like recess 13 to accommodate a flanged portion 3a (see FIG. 10) formed by burring.
In the conventional terminal devices described above, the box terminal device and the terminal device for a press terminal have their respective exclusive frames produced independently of each other. Therefore, for example, the frame for the box terminal device can not be used for the terminal device for the press terminal. Thus, when a connection system is changed after installation of an electrical apparatus, the whole apparatus has to be replaced.
In view of the problems described above, it is an object of the invention to provide a terminal device in which it is possible to easily switch between a cable with a stripped end and a cable with a press terminal.
Further objects and advantages of the invention will be apparent from the following description of the invention.